xfce-git: Run autogen.sh in source directory
The autogen.sh script executed by the xfce-git.bbclass needs to be
run in and from the source directory. The configuration step can
still be run from out-of-tree.
Currently, this affects these recipes:
* libxfce4ui
* xarchiver
* xfce4-taskmanager
* xfce4-closebutton-plugin
* xfce4-settings
* xfwm4
Upstream-Status: Inappropriate (configuration)
Signed-off-by: Ash Charles <ashcharles@gmail.com>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>